31331222213 has 2 divisors, whose sum is σ = 31331222214. Its totient is φ = 31331222212.

The previous prime is 31331222147. The next prime is 31331222233. The reversal of 31331222213 is 31222213313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30459673729 + 871548484 = 174527^2 + 29522^2 .

It is a cyclic number.

It is not a de Polignac number, because 31331222213 - 2²² = 31327027909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31331222233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15665611106 + 15665611107.

It is an arithmetic number, because the mean of its divisors is an integer number (15665611107).

Almost surely, 2^31331222213 is an apocalyptic number.

It is an amenable number.

31331222213 is a deficient number, since it is larger than the sum of its proper divisors (1).

31331222213 is an equidigital number, since it uses as much as digits as its factorization.

31331222213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 23.

Adding to 31331222213 its reverse (31222213313), we get a palindrome (62553435526).

The spelling of 31331222213 in words is "thirty-one billion, three hundred thirty-one million, two hundred twenty-two thousand, two hundred thirteen".